Method for improving operational reliability of electric machine

Abstract

A method for improving the running reliability of a motor comprises the following steps that (1) a triode is arranged between a grid driving chip and a power supply of the grid driving chip and used for controlling the on-off state of the power supply of the grid driving chip; 2) setting a register configuration upper limit value for judging the register configuration condition of the gate driving chip; 3) electrifying the gate driving chip, and configuring each register of the gate driving chip according to actual requirements and a data manual of the gate driving chip; 4) the master control chip of the motor inverter performs read-back judgment on all registers of the gate drive chip: 4-1) if all registers of the gate drive chip fail to be configured, the gate drive chip is controlled to be powered off, and the step 3) to the step 4) are repeated until the number of times of register configuration failure reaches the register configuration upper limit value; and 4-2) if all registers of the gate driving chip are successfully configured, driving the motor by using the inverter after successful configuration of the gate driving chip.

Description

Technical Field

[0001] The present invention relates to the field of motor control, and in particular to a method for improving the reliability of motor operation. Background Art

[0002] With the rise of new energy vehicles, there are great opportunities in the three-electric field of automobiles. Among them, the traction motor responsible for the power of the vehicle body cannot be directly driven by a low-power DC source. Therefore, this traction motor must use an inverter to convert DC into high-power AC for driving.

[0003] The inverter currently used to drive the motor usually uses a gate driver chip to convert the MCU's low-voltage PWM into a high-current gate drive signal, thereby driving high-power transistors such as IGBTs and SiC power devices, further driving the traction motor.

[0004] However, most of the current gate driver chip driving methods directly put the gate driver chip into use after the register of the gate driver chip is configured once, regardless of whether the configuration is successful.

[0005] If the gate driver chip configuration register in the inverter fails to drive the gate driver chip in this way, the following situations may occur, causing the motor to fail to operate normally: ① Abnormal drive signal: Failure to provide the correct gate drive signal to the power device causes the power device to fail to turn on and off normally, thus failing to achieve effective conversion from DC to AC.

[0006] ② Failure of protection function: It may not be possible to detect and respond to abnormal conditions such as overcurrent and overvoltage in a timely manner, which may damage the power devices or even the entire inverter, thus affecting the operation of the motor.

[0007] In summary, once the gate drive chip configuration register fails, the gate drive chip cannot work according to the preset correct parameters and mode, and the motor will operate abnormally, resulting in unstable motor torque, excessive current, abnormal speed and other problems. If not resolved in time, safety accidents such as motor overheating, damage or system failure may eventually occur. Summary of the invention

[0008] The purpose of the present invention is to provide a method for improving the reliability of motor operation in view of the corresponding deficiencies in the prior art. A transistor is arranged between a gate drive chip in a motor inverter and a power supply of the gate drive chip, so that a main control chip can realize power-on and power-off control of the gate drive chip by controlling the transistor, and disconnect the power supply of the gate drive chip after the register configuration of the gate drive chip fails, so that the gate drive chip is restarted, and the register configuration of the gate drive chip is repeatedly checked to make the gate drive chip configuration successful as much as possible, thereby improving the reliability of motor operation, thereby avoiding the occurrence of safety accidents such as motor overheating, damage or system failure.

[0009] The object of the present invention is to adopt the following scheme to achieve a method for improving the reliability of motor operation, comprising the following steps: 1) A transistor is arranged between the gate drive chip in the motor inverter and the power supply of the gate drive chip, and the base of the transistor is connected to the control signal output terminal of the motor inverter main control chip to control the power on and off of the gate drive chip; 2) Set a register configuration upper limit value to determine the register configuration of the gate drive chip; 3) Power on the gate driver chip and configure the registers of the gate driver chip according to actual needs based on the gate driver chip data sheet; 4) The main control chip of the motor inverter reads back all the registers of the gate drive chip to make judgments: 4-1) If all register configurations of the gate driver chip fail, the gate driver chip is powered off and steps 3) to 4) are repeated until the number of register configuration failures reaches the upper limit of the register configuration; 4-2) If all registers of the gate drive chip are configured successfully, the motor is driven by the inverter after the gate drive chip is configured successfully.

[0010] Preferably, a first resistor is provided between the base and the emitter of the transistor to prevent the transistor from being mis-conducted.

[0011] Preferably, a second resistor is provided between the base of the transistor and the control signal output terminal of the motor inverter main control chip for current limiting to prevent the transistor from being burned out due to excessive base current.

[0012] Preferably, the transistor is a PNP transistor, the collector of the PNP transistor is connected to the pin on the gate drive chip for connecting the positive pole of the power supply, the emitter is connected to the positive pole of the power supply, and the negative pole of the power supply is connected to the pin on the gate drive chip for connecting the negative pole of the power supply through a third resistor, so as to suppress noise and perform current limiting protection on the chip.

[0013] Preferably, the transistor is an NPN transistor, the collector of the NPN transistor is connected to the pin on the gate drive chip for connecting the negative pole of the power supply, the emitter is connected to the negative pole of the power supply, and the positive pole of the power supply is connected to the pin on the gate drive chip for connecting the positive pole of the power supply through a third resistor, so as to suppress noise and perform current limiting protection on the chip.

[0014] Preferably, in step 4), before reading back all registers of the gate driver chip for judgment, the fault bits of each status register should be cleared to eliminate false alarm faults during the initialization process.

[0015] Preferably, in step 4-1), the specific method of determining whether the register configuration has failed is to use the main control chip to read back and verify the address bit, data bit and check bit of the register. If any bit (i.e., one of the address bit, data bit and check bit) of any register fails to be verified, the main control chip determines that the register configuration has failed.

[0016] Preferably, in step 4-1), after the number of register configuration failures reaches the register configuration upper limit, a fault code is reported to the main control chip of the motor inverter according to the value in the gate drive chip status register.

[0017] The advantages of the present invention are the following three points: ① After all registers of the gate drive chip are configured, the main control chip reads back the address bit, data bit and check bit values ​​of each register of the gate drive chip to determine whether the register of the gate drive chip is configured successfully, so as to ensure the reliability of subsequent motor operation; ② The present invention sets a transistor between the gate drive chip in the motor inverter and the power supply of the gate drive chip, so that the main control chip can realize the power-on and power-off control of the gate drive chip by controlling the transistor, and disconnect the power supply of the gate drive chip after the register configuration of the gate drive chip fails, so that the gate drive chip is restarted, and the register configuration of the gate drive chip is repeatedly checked to make the gate drive chip configuration successful as much as possible, thereby improving the reliability of motor operation and avoiding the occurrence of safety accidents.

[0018] ③ The present invention can greatly improve the reliability of motor operation by simply adding a transistor to the original circuit at a very low cost.

[0019] Glossary MCU: Microcontroller Unit, is an integrated circuit chip that integrates processor core, memory, timer, counter, input and output interface, etc. In the present invention, it refers to the main control chip of the inverter.

[0020] PWM: Pulse Width Modulation, is a commonly used digital signal modulation technology.

[0021] IGBT: Insulated Gate Bipolar Transistor, is a composite fully controlled voltage-driven power semiconductor device.

[0022] SiC power devices: such as SiC MOSFET (metal-oxide semiconductor field-effect transistor), SiC diode, etc. Compared with traditional silicon-based devices, SiC power devices can operate at higher temperatures, voltages and frequencies, have lower on-resistance and switching losses, thereby improving system efficiency and power density.

[0023] Power off / power on: refers to the process of powering off or powering on an electronic device. In the present invention, it is to instruct the gate drive chip to power off or power on.

[0024] GD3160: is an improved advanced single-channel high-voltage isolated gate driver with enhanced driving and protection functions for Silicon Carbide (SiC) MOSFETs. SPI programmable driving, protection and fault reporting functions allow. GD3100 and GD3160 are chips of the same series with different models, and their functions are not much different.

[0025] Read back: in the present invention, it refers to the action of the main control chip re-reading the gate drive chip register data. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a flow chart of the present invention; Figure 2 It is a schematic diagram of the arrangement of the triode of the present invention; Figure 3 Schematic diagram of the circuit structure of embodiment 1 of the present invention; Figure 4 Schematic diagram of the circuit structure of embodiment 2 of the present invention. DETAILED DESCRIPTION

[0027] like Figure 1 As shown, a method for improving the reliability of motor operation includes the following steps: 1) A transistor is arranged between the gate drive chip in the motor inverter and the power supply of the gate drive chip, and the base of the transistor is connected to the control signal output terminal of the motor inverter main control chip to control the power on and off of the gate drive chip; Usually, a first resistor can be set between the base and emitter of the transistor to prevent the transistor from being mis-conducted. A second resistor can also be set between the base of the transistor and the control signal output end of the motor inverter main control chip to limit the current to prevent the base current from being too large and burning the transistor, and to reduce the influence of temperature on the transistor to make the transistor work stably.

[0028] The transistor can be an NPN transistor or a PNP transistor. The specific connection methods of the two different types of transistors with the gate drive chip and the power supply are as follows: If the transistor is a PNP transistor, the collector of the PNP transistor is connected to the pin on the gate drive chip for connecting the positive pole of the power supply, the emitter is connected to the positive pole of the power supply, and the negative pole of the power supply is connected to the pin on the gate drive chip for connecting the negative pole of the power supply through a third resistor, so as to suppress noise and perform current limiting protection on the chip.

[0029] If the transistor is an NPN transistor, the collector of the NPN transistor is connected to the pin on the gate drive chip for connecting the negative pole of the power supply, the emitter is connected to the negative pole of the power supply, and the positive pole of the power supply is connected to the pin on the gate drive chip for connecting the positive pole of the power supply through a third resistor, so as to suppress noise and perform current limiting protection on the chip.

[0030] 2) Set a register configuration upper limit value to determine the register configuration of the gate drive chip; 3) Power on the gate driver chip and configure the registers of the gate driver chip according to actual needs based on the gate driver chip data sheet; 4) First, clear the fault bits of each status register to eliminate false alarms during the initialization process. Then, the main control chip of the motor inverter reads back all the registers of the gate drive chip to determine: 4-1) If all register configurations of the gate driver chip fail, the gate driver chip is powered off and steps 3) to 4) are repeated until the number of register configuration failures reaches the upper limit of the register configuration; The specific way to judge the register configuration failure is to use the main control chip to read back and check the address bit, data bit and check bit of the register. If any bit (one of the address bit, data bit and check bit) of any register fails to be checked, the main control chip judges that the register configuration has failed. Usually, after the main control chip judges that the register configuration has failed, it will also report the fault code to the main control chip of the motor inverter according to the data in the gate drive chip status register, so that the system can display the specific cause of the fault.

[0031] 4-2) If all registers of the gate drive chip are configured successfully, the inverter after the gate drive chip is configured successfully is used to drive the motor.

[0032] According to the above method, the register configuration upper limit value is set to 3, and Infineon TC387 is used as the main control chip MCU, and the gate drive chips GD3100 and GD3160 of the semiconductor company NXP Semiconductors are used, and Examples 1 and 2 are respectively as follows: Example 1: Using a PNP transistor of model BC856-Q like Figure 3 As shown, a first resistor R1 is provided between the base b and the emitter e of the transistor, and the resistance of the first resistor R1 is 20k ohms. The control signal output pin IO of the main control chip MCU is connected to the base b of the PNP transistor through the second resistor R2, and the resistance of the second resistor R2 is 10k ohms. The collector c of the transistor is connected to the pin VDD of the gate drive chip GD3100, and the emitter e is connected to the positive electrode VDD of the power supply. The voltage of the power supply is 15V, and the negative electrode of the power supply is grounded. Therefore, the ground pin GND of the gate drive chip GD3100 is grounded through the third resistor R3, and the resistance of the third resistor R3 is 10k ohms.

[0033] Use +5V power supply VCC to power the main control chip, and connect the communication port of the main control chip MCU to the communication port of GD3100, so that the main control chip MCU can configure or read the register data of GD3100 through the communication port.

[0034] Configuration and verification process of gate driver chip GD3100: After the gate driver chip GD3100 is powered on, configure the various registers of the gate driver chip according to the actual needs according to the gate driver chip data manual; after all registers are configured, clear the data of the fault bit of each status register, re-read the data of each register of GD3100, and check the address bit, data bit and CRC bit of all register data.

[0035] The main control chip MCU found that the address bit of a register of the gate driver chip GD3100 failed to be verified. At this time, the main control chip MCU determined that the register configuration failed. The main control chip immediately controlled the transistor to cut off the power supply to the gate driver chip GD3100, and repeated the configuration and verification process of the gate driver chip GD3100 many times, but still failed to successfully configure the register of the gate driver chip GD3100.

[0036] When the register configuration times reaches three times, the main control chip MCU reports the fault code to the main control chip of the motor inverter according to the data in the gate driver chip status register, allowing the system to display the specific cause of the fault - "Gate driver chip GD3100 register configuration failed, unable to start the motor", and actively cuts off the power supply of the motor, thereby avoiding safety accidents such as motor overheating, damage or system failure.

[0037] Example 2: Using NPN transistor model BC846-Q like Figure 4 As shown, a first resistor R4 is provided between the base b and the emitter e of the transistor, and the resistance of the first resistor R4 is 20k ohms. The control signal output pin IO of the main control chip MCU is connected to the base b of the NPN transistor through the second resistor R5, and the resistance of the second resistor R5 is 10k ohms. The voltage of the power supply is 15V, and the positive electrode of the power supply is connected to the pin VDD of the gate drive chip GD3160 through the third resistor R6 with a resistance of 10k ohms. The negative electrode of the power supply is grounded, so the ground pin GND of the gate drive chip GD3160 is connected to the collector c of the transistor, and the emitter e of the transistor is grounded.

[0038] Use +5V power supply VCC to power the main control chip, and connect the communication port of the main control chip MCU to the communication port of GD3160, so that the main control chip MCU can configure or read the register data of GD3160 through the communication port.

[0039] Configuration and verification process of gate driver chip GD3160: After the gate driver chip GD3160 is powered on, the various registers of the gate driver chip are configured according to the actual needs according to the gate driver chip data manual; after all registers are configured, the data of the fault bits of each status register are cleared, and the data of each register of GD3160 is re-read, and the address bits, data bits and CRC bits of all register data are checked.

[0040] The main control chip MCU found that the data bit check of a register of the gate drive chip GD3160 failed, and the main control chip MCU judged that the register configuration failed. The main control chip immediately controlled the transistor to cut off the power supply to the gate drive chip GD3160, and repeated the configuration and verification process of the gate drive chip GD3160 again. The main control chip was used to read back the address bit, data bit and check bit of the register. It was found that this time the address bit, data bit and check bit of all registers of the gate drive chip GD3160 were successfully verified, and the main control chip judged that the register configuration was successful. After testing, the inverter after the gate drive chip GD3160 was successfully configured can stably drive the motor to work.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification made to the present invention by those skilled in the art without departing from the spirit of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for improving the reliability of motor operation, characterized in that: The following steps are involved: 1) A transistor is arranged between the gate drive chip in the motor inverter and the power supply of the gate drive chip, and the base of the transistor is connected to the control signal output terminal of the motor inverter main control chip to control the power on and off of the gate drive chip; 2) Set a register configuration upper limit value to determine the register configuration of the gate drive chip; 3) Power on the gate driver chip and configure the registers of the gate driver chip according to actual needs based on the gate driver chip data sheet; 4) The main control chip of the motor inverter reads back all the registers of the gate drive chip to make judgments: 4-1) If all register configurations of the gate driver chip fail, the gate driver chip is powered off and steps 3) to 4) are repeated until the number of register configuration failures reaches the upper limit of the register configuration; 4-2) If all registers of the gate drive chip are configured successfully, the inverter after the gate drive chip is configured successfully is used to drive the motor.

2. The method for improving the reliability of motor operation according to claim 1, characterized in that: A first resistor is provided between the base and the emitter of the triode to prevent the triode from being mis-conducted.

3. The method for improving the reliability of motor operation according to claim 1, characterized in that: A second resistor is provided between the base of the transistor and the control signal output terminal of the motor inverter main control chip, which is used for current limiting to prevent the transistor from being burned out due to excessive base current.

4. The method for improving the operating reliability of a motor according to claim 1, characterized in that: The transistor is a PNP transistor, the collector of which is connected to a pin on a gate drive chip for connecting to the positive electrode of a power supply, the emitter is connected to the positive electrode of the power supply, and the negative electrode of the power supply is connected to a pin on a gate drive chip for connecting to the negative electrode of the power supply through a third resistor, so as to suppress noise and perform current limiting protection on the chip.

5. The method for improving the operating reliability of a motor according to claim 1, characterized in that: The transistor is an NPN transistor, the collector of which is connected to a pin on a gate drive chip for connecting to the negative pole of a power supply, the emitter is connected to the negative pole of the power supply, and the positive pole of the power supply is connected to a pin on a gate drive chip for connecting to the positive pole of the power supply through a third resistor, so as to suppress noise and perform current limiting protection on the chip.

6. The method for improving the operating reliability of a motor according to claim 1, characterized in that: In step 4), before reading back all the registers of the gate driver chip, the fault bits of each status register should be cleared to eliminate false alarms during the initialization process.

7. The method for improving the operating reliability of a motor according to claim 1, characterized in that: In step 4-1), the specific method of determining that the register configuration has failed is to use the main control chip to read back and verify the address bit, data bit and check bit of the register. If any bit of any register fails to be checked, the main control chip determines that the register configuration has failed.

8. The method for improving the operating reliability of a motor according to claim 1, characterized in that: In step 4-1), when the number of register configuration failures reaches the upper limit of the register configuration, a fault code is reported to the main control chip of the motor inverter according to the value in the gate driver chip status register.

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